Indoles, nucleosides and their analogues have been used in the treatment of viral infections in mammals, including humans. Viruses that infect mammals and are treatable by the administration of pharmaceutical compositions comprising indoles, nucleosides or their analogues or derivatives include hepatitis C virus (HCV), human immunodeficiency virus (HIV), pestiviruses, and flaviviruses (Moennig et al., Adv. Vir. Res. 1992, 41:53-98; Meyers and Thiel, Adv. In Viral Res. 1996, 47:53-118; Moennig et al., Adv. Vir. Res. 1992, 41:53-98; Halstead, Rev. Infect. Dis. 1984, 6:251-64; Halstead, Science 1988, 239:476-81; Monath, New Engl. J. Med. 1988, 319:641-3).
PCT Publication No. WO 2004/014364 to Idenix Pharmaceuticals discloses a class of phenylindoles that display enhanced anti-HIV activity. These compounds are substituted with at least two moieties on the phenyl ring and/or the benzo ring of the indole functionality. In addition, these compounds incorporate a number of substituents having a carboxamide functionality at position-2 on the indole group of the compounds.
Idenix Pharmaceuticals also disclosed another class of phenylindole compounds, including phosphophenylindoles, for the treatment of HIV and/or AIDS (US 2006/0074054 and WO 06/054182).
In light of the fact that HIV infections have reached epidemic levels worldwide and have tragic effects on infected hosts, there remains a strong need to provide new and effective pharmaceutical agents, but with low toxicity, to treat these viral infections.